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Food Irradiation Updates

  
Published by Ronald F. Eustice and sponsored  by GRAY*STAR Inc.
August 2015
Food Irradiation Update is published monthly by Ronald F. Eustice, a food quality & safety assurance consultant based in Tucson, Arizona. He can be reached at:
and at 612.202.1016
Good News Everywhere! With the passing of each month the news about irradiation of food gets better. Exports of irradiated mangoes from India to the US have reach record levels. Vietnam is expected to export US$2 billion of lychees in 2015 and Russia has made a major commitment to expand the use of irradiation in India. Irradiated Australian mangoes are selling well in the US and New Zealand and the list of eligible fruit is expanding rapidly. Irradiated Mexican figs have arrived in the US. We have seen the export of irradiated blueberries from the US to United Arab Emirates and India. The irradiation of oysters is rapidly becoming a routine practice. Exciting Times!

IN THIS ISSUE

FEATURED ARTICLE: Why Irradiate?  By Russell N. Stein

Russell Stein inside a Genesis pool being fabricated

My first experience with irradiated food was in 1958...a few months before I was born.  My father was a scientist and a soldier in the US Army.  He was posted to the Quartermaster Corps in Chicago to work on the development of irradiated foods for potential use by the military. 

Surplus irradiated food from tasting studies found their way to my pregnant mother. And ultimately to the ravenous parasite living in her womb...me.

 

Am I biased on the subject of radiation processing?  Yes.  Biased by knowledge and experience.  If we discount this bias, we are only left with faith.  Food Irradiation is not a religion.  It is simply one of many technologies that can benefit human health and wellbeing.  

My entire life I have heard why food irradiation is bad, even evil.  These arguments are not based on knowledge or experience, but on faith.  Faith that anything to do with "radiation" or anything "nuclear" is unnatural and was created by greedy men solely to make money.  By definition, for the faithful, faith will trump knowledge and experience in any argument.  Thus, irradiation processing should not exist.

 

And yet products, including food, are irradiated on a daily basis around the world.  These products are not irradiated because the decision makers like "radiation" or like "nuclear" stuff.  They are not irradiated to make them rich.  Heck, they have to spend money to have things irradiated.  So why do companies spend money to irradiate their products?  The answer is simple...the process works.  

 

Those that have chosen to irradiate their product to make them safer or better know that they can rely on the process.  It can take years for someone to break the faith that irradiation is bad before they try using irradiation on their products.  But, once they do, they continue to use the process for years, decades.  It becomes just another routine part of the process of bringing their product to market.

 

Why are they willing to use irradiation? Irradiation has four amazing qualities.  These are because irradiation uses energy.  Energy that is very efficient and reproducible.  

 

The first quality is that the process is very gentle.  It has minimal effect on the product.  Because the process does not significantly heat the product, irradiated raw product is still raw.  Irradiated frozen product is still frozen.  Irradiation is so efficient that it does not significantly affect proteins and other components of food that would alter its physical nature.  Because irradiation is a gentle process, it is not surprising that it does not make the food unsafe.  Heat is also energy, but heat is far from gentle.

 

The second quality is that irradiation penetrates through packaging deep into the product. Therefore, the product can be irradiated in its final package (including retail packaging). This quality decreases the possibility of recontamination from the environment during storage and distribution.

 

The third quality is that irradiation systems ("irradiators") are designed to deliver and monitor the radiation energy to the product consistently.  There is great assurance that all of the product will receive the dose of radiation specified.  And that means that all of the pathogens will receive that same dose.  

 

Finally, gamma irradiators in use today are robust.  The life of irradiators is measured in decades.  They are designed to run 24 hours a day, 365 days per year.  

For the last 50 years we have heard an overwhelming number of negative comments on irradiation.  And yet, for the last 50 years irradiation has been employed by many companies for the benefit of their customers.  

Why irradiate?  Because it works.

MYTH of the MONTH:"irradiated foods taste bad." By Russell Stein

Myth: 

"Irradiated foods taste bad."


Reality:

Some foods irradiated at certain doses can have flavor changes.  However, if they have a bad taste they will not be marketable.  Therefore, irradiated food that is sold in stores does not taste bad.


The irradiation of food is a gentle process when compared to other processes such as heating.  Normally, there is very little effect on the food.  For some foods, there are effects on taste that are detectable at certain dose levels.


When a company is interested in irradiating their food product they test samples of the food by irradiating them to the highest dose that they would expect commercial lots of the food to receive.  They need to handle these samples as close as practical to the way that they would handle commercial product.  Product handling and shipping might have an effect on the food product that is independent from the irradiation process.  When performing these tests, it is also important to send a control sample along with the samples to be irradiated.  This control should be treated as close as practical to the samples that are irradiated...effectively irradiated to a zero dose.  A second control sample should be kept at the place of origin to be able to compare this sample with both the irradiated samples and the "zero dose" control sample.  By using this approach, the food company can determine if the handling, shipping and/or the irradiation has had any effect on their product.  Often these effects can be minimized or eliminated by changing the way the product is handled.


Once a company has tested their product, under their handling conditions, they need to evaluate the product to determine if there are any effects.  More importantly, if there are any effects, they need to determine if those effects would have a negative impact on marketing the product.  Obviously, if they do, then they would not market the product.   Sometimes there are negative effects that are minimal (would not affect the marketing of the product) or positive effects that might actually enhance the marketing of the product.  The important point is that if a food company determines that there is a significant negative effect on their product, it would not be marketed and therefore, not available to consumers.  A company is not going to sell a food product that has a bad taste.


Many years ago when it was realized that there may be advantages to irradiating food, extensive "basic" research was performed.  Food was irradiated at very high doses to determine what effects the irradiation had on food.  One of the questions was how high a dose could a specific food be irradiated to before developing a bad taste?  Obviously, to determine this dose, it was required to irradiate the test samples until a bad taste was detected.  This leads to a statement that I hear quite often:  "I've read that irradiated [fill in your favorite food] taste horrible!"  That leads to my questions:  "What was the dose that it was irradiated at, and under what conditions, such as temperature?"  Similarly, any food will also taste bad if overcooked.  If a hamburger was cooked at 600 degrees for an hour, I'm sure you would not find it on the menu at your local burger joint.  Does this mean that we shouldn't be able to buy properly cooked hamburgers?


Irradiation may have a negative impact at a certain dose on specific foods.  If they do, then they will not be marketed.  However, this should never be used as an excuse not to allow the use of irradiation on food.  If this argument were used on the cooking of hamburgers, our Labor Day menu would be severely impacted.


On a side note, sometimes the irradiation of certain foods has a positive effect on taste.  Personally I prefer the taste of irradiated crab meat.  But, then again, I love creamed succotash!

Link to article ... 

Russell N. Stein

GRAY*STAR, Inc.

www.GrayStarInc.com

Also in the News: First shipment of Mexican figs arrive in the US; Fresh Plaza (July 30, 2015):
After a deal was reached earlier this year allowing the shipment of Mexican figs into the United
Mexican figs are irradiated
States, the first amounts of Mexican fruit have now reached U.S. markets, says a release from SAGARPA, dated July 23. With the U.S. market now open to Mexican exporters, plantings of figs in Mexico could increase.

The first shipment was 257 kilograms of fresh figs that were treated and irradiated, per the agreement reached between the U.S. Department of Agriculture and its Mexican equivalent. The first figs sent came from production in the Mexican states of Morelos and Puebla. Following the first shipment, a second load of 628 kilograms of fresh figs was sent.

There are currently 200 hectares of production in Mexico, mostly in Morelos, Baja California Sur, Puebla and Hidalgo. That acreage could increase should Mexican exporters find success with subsequent shipments. Current national production is estimated at just over 6,000 tonnes of figs valued at about US$3 million.

Source: Secretary of Agriculture, Livestock, Rural Development, Fishing and Food (SAGARPA)
Also in the News: Sweet success for Vietnam lychees; Vietnam Net Bridge (July 28, 2015):
Vietnam will export US$2 Billion of lychees in 2015

Every year, in June and July, anyone visiting Luc Ngan district in Bac Giang province will see its streets bursting with the red of ripe lychees. This year Luc Ngan saw a rich harvest, with its growers happier than in previous seasons because their lychees are now officially allowed to be exported to the US and Australia after many years of negotiations and quality tests. 

 

Not only Luc Ngan but also famed Thanh Ha lychees, from Hai Duong province, are to be exported to the two markets. Farmers are happy and the government is excited because after so much effort Vietnamese lychees have finally reached the quality standard for export to the markets, which are considered to among the largest and most fastidious in the world.

 

From June 12 to 19, 12 tons of lychees from the Red Dragon Company arrived in the Australian city of Melbourne, while one ton from the Thien Anh Minh Company and 3.5 tons from the Anh Sao Duong Company found their way to Sydney. After 12 years of negotiations it's expected that Australian importers will sign larger contracts and greater opportunities will open up for Vietnamese lychees in the country. 

 

Meanwhile, on May 30 over 2.1 tons of lychees were taken straight from Noi Bai International Airport to Ho Chi Minh City for irradiation and quality quarantine before being exported to the US. According to exporters, although the US now receives two types of lychees - from China and Mexico - the Vietnamese variety is appreciated for its appealing taste. Experts believe that the pioneers in exporting lychees to the US and Australia need to present clean agricultural brands in the tough markets, which will drive the development of sustainable agriculture exports.

 

Positive signs 

Exports are on the rise, in traditional markets such as China, Laos, Cambodia, Thailand, Singapore and Europe, as well as tough markets like Japan and South Korea. China still remains the largest importer, accounting for 60 per cent of total export volumes.

Ms. Nguyen Thi Hoang Thuy, Trade Representative of Vietnam in Australia, expressed her pleasure at Vietnamese lychee being officially exported to the country. She believes the exports are extremely important because Australia has strict quarantine regulations. "Once we successfully negotiated lychee exports the door for other fruit exports to Australia became wide open," she was quoted as saying. 

 

While most companies agree that exporting lychees to foreign markets, especially the US and Australia, is anything but easy due to competition with other countries, Ms. Nguyen Thi Man, Director of the Thanh Ha Agricultural Product Processing and Export Co. in Hai Duong province, who has seven years experience in lychee exports, believes Vietnamese lychee holds advantages in the US because it is sweeter and more aromatic. "Mexico's have a lighter taste, with 13 per cent sugar, while Vietnam's has 19 to 20 per cent sugar," she said. With many years of experience with South Korean partners, she also emphasized that foreigners often attach great importance to reputation. Vietnamese enterprises wanting to promote exports to foreign countries, therefore, need to retain their credibility.

 

With positive signs from foreign export markets, lychee growers this year no longer have to worry about reaping bumper crops then experiencing lower prices, as has been the case in the past. Ms. Nguyen Thi Dung, a lychee grower in Luc Ngan, said that this season her family harvested about half of a ton of lychee grown under export standards. Exporters paid VND15,000 ($0.69) to VND20,000 ($0.93) per kilogram, which is higher than the price in the domestic market, and her family saw better earnings this year. It's clear to see that the positive signs for lychees going to the US and Australia as well as plans to continue the export of apples, dragon fruit, rambutan, and mango to difficult markets like the US, Japan, Australia, and New Zealand presents a good opportunity for Vietnamese fruit to conquer global markets.

 

Difficulties ahead

Despite the positive signs, the export of lychee into the two new markets is still believed to face many difficulties. According to Deputy Minister of Industry and Trade Tran Tuan Anh, the first lychee shipments to the US and Australia are just an initial step. "We can't expect too much because these shipments are just a test run," he said. "This year lychee growers must still depend on domestic consumption and the Chinese market." He also indicated that in strict and fastidious markets it takes at least five to eight years or even longer for fruit to penetrate successfully. Vietnamese lychee took 12 years to be accepted in Australia. "Therefore, we shouldn't hope that in the next one or two years Vietnam will have a large share of the lychee market in the US, Australia, or Europe," he said.

 

Meanwhile, a lack of information on foreign market continues to create difficulties for Vietnamese exporters, Ms. Man said. Enterprises wanting to promote their exports must conduct research to understand the market and their partners. "The role of commercial counselors is particularly important, and product quality needs to be the top priority," she added. The Export and Import Department under the Ministry of Industry and Trade, in its report on fruit and vegetable exports in May, noted that the ability of exporters to follow export processes remains weak, especially in negotiating, transporting, and handling. Because of these weaknesses domestic enterprises are still to secure major contracts, according to the report.

 

The building of a reputation for quality and improved storage of fruit are now more necessary than ever. The lessons from Vietnam's dragonfruit exports to Japan must be learned. After the first shipment, a Japanese consumer found a worm in a dragonfruit she purchased and the fruit was immediately banned and it took ten more years before exports resumed. The journey the Vietnamese lychee has taken, with its many years of trouble with recurring instances of bumper crops and low prices, brought it to the most difficult markets in the world but also the ones with the most potential. Exporters need to be reminded yet again about the value of establishing a reputation for constant quality in production, processing and preservation.  

 

Deputy Minister of Industry and Trade Tran Tuan Anh: "MoIT recognizes that boosting the provision of information to businesses is very important. It therefore requested its E-commerce and Information Technology Department cooperate with the Export and Import Department to build a comprehensive information system for businesses, to support them in their agricultural exports. Enterprises will receive regular information on foreign markets to meet the demands of their partners."

 

Ms. Tran Thi Phuong Lan, Deputy Director of the Hanoi Department of Industry and Trade: "From production to circulation there are difficulties, so the department will create links between agricultural regions and between farmers and enterprises, to help them improve their operations and ensure that the quality of their fruit is always high before they are exported."

 Link to article ...

Also in the News: Russian firm Rosatom targets India irradiation network; India Express (July 27, 2015):
Irradiation will help increase food security in India by preventing sprouting of onions, potatoes and other tubers.

Broad basing its atomic sector cooperation with India, an affiliate of Russian state-owned nuclear firm Rosatom State Corp has picked up a 51 per cent stake in Tamil Nadu-based Gamma Tech India Private Ltd. to jointly implement a project that aims to set up a network of radiation sterilisation centres across India. The centres to be developed by Rusatom Overseas JSC will offer food decontamination and sterilisation of medical products by ionizing radiation, including sterilisation of medical products such as latex gloves, decontamination of fruit, berries and other products exported from India to developed countries.

 

The centres will be constructed in Tamil Nadu, Kerala, Karnataka, Andhra Pradesh and Maharashtra and the first pilot centre is planned to be established in Tamil Nadu. This is the first such major intervention by a foreign government nuclear utility in India, one of the largest food producers in the world with about 600 million tonnes of food products generated every year. The approval by the Indian nuclear regulator - the Atomic Energy Regulatory Board of India or AERB - for the irradiation equipment design and the construction of the first irradiation centre has already been obtained.

 

"Currently, the project is in its pre-investment phase with the internal corporate procedures being undertaken, after which the investment phase of the project will start," Ksenia N Loskutova of the strategic communications unit of Moscow-based Rusatom Overseas JSC said in response to a query from The Indian Express.

 

Loskutova stated that in the first stage, it is planned to construct one pilot irradiation centre with two facilities that will provide services of food decontamination and sterilisation of medical products. "The project is currently at an advanced stage: the memorandum of understanding with the AERB has been signed, the approval by the AERB of the irradiation equipment design and irradiation centre construction has been obtained among other permits. The pilot centre will occupy an area of approximately 2 hectares at the Chezhianallur Village near Tirunelveli, Tamil Nadu," she stated in an email response.

Currently, Rusatom Overseas is about to finish the construction of two radiation sterilisation centres in Russia. "When the radiation sterilisation centres in India become operational, we will get a great example of competitive product solution by Rosatom State Corporation in terms of specialised radiation centres not only in our country but also abroad," Dzhomart Aliev, CEO of Rusatom Overseas, said. A query sent to Gamma Tech on the issue did not elicit a response.

 

Radiation sterilisation is a physical process of irradiation of medical products by ionizing radiation. Products are subjected to irradiation in specialised radiation technology facilities where gamma-rays (gamma-rays of Co-60 or Cs-137 isotopes) or electron accelerators are used. When electrons go through the material substance, most of their energy is spent on ionization, which results in destruction of micro-organisms and a reduction in the number of pathogenic bacteria and viruses.

 

The process of radiation sterilisation is the final stage of production of single-use medical products. These technologies can be used in agriculture, as well as for municipal solid waste sterilisation and in the petrochemical industry. Over 42 countries in the world including the US, the UK, Canada and France have given clearance for radiation processing of food.

 

The Government of India has permitted the use of radiation technology in preservation of food items such as potato, onion, rice semolina, wheat flour, mango, raisins, dried dates, ginger, garlic, shallots (small onions) as well as meat and meat products including chicken.

 

The Mumbai-based Bhabha Atomic Research Centre has done extensive research and development work on preservation of food by radiation and has been involved in setting up the first demonstration plant for radiation processing of onions and potatoes at Lasalgaon in Nasik, Maharashtra. The same plant is also proposed to be used for low dose radiation processing of other foods with alterations in throughput and source utilisation efficiency.

Link to article ...
India mango exports reach record levels of 328 metric tonnes; The Times of India (July 25, 2015):
India exported 328 MT of mangoes to the US in 2015...a Record!
NASHIK, INDIA: The irradiation centre of Bhabha Atomic Research Centre (BARC) at Lasalgaon, about 70km from Nashik, has irradiated a record 328 metric tonnes of mangoes for export to the US in the current mango season. The centre had treated 295 metric tonnes of mangoes in the same period last year. 

As per the US norms, it is mandatory to irradiate the king of fruits before is shipped off to the US. The Lasalgaon facility has capacity of treating around seven metric tonnes of mangoes in eight-hour shift. . 

Speaking to TOI, an official from the Agrosurg Irradiators India, said, "We had set a target of treating 400 tonnes of mangoes this year, but had to settle with 328 as the season ended earlier this year due to bad weather." 

Meanwhile, the centre has applied for licence to treat cereals, pulses, spices and dry fruits. "We already have a licence for irradiating vegetables and fruits. Now we have applied to the Department of Atomic Energy to get licenses for treating cereals, pulses, spices and dry fruits," the official said, adding that as the mango season is over, the centre is in the process of increasing its capacity from the present 200 kilo curies (kCi) to 290 kCi of cobalt. Earlier the capacity of Lasalgaon irradiation was 300 kCi which reduced over a period of time as operation picked up here. 

The BARC had set up the irradiation centre known as Krushak- Krushi Utpadan Sanrakshan Kendra at Lasalgaon to treat agricultural commodities for their preservation in 2002. The plant was dedicated to the nation by the then Prime Minister Atal Bihari Vajpayee on October 31, 2002. This irradiation facility at Lasalgoan is commercially operated by the Vasai-based Agrosurg Irradiators India Pvt Ltd. 
Comparative Evaluation of the Effect of Methyl Bromide Fumigation and Phytosanitary Irradiation on the Shelf Life of Air Freighted Strawberries; Institute of Food Technologists; Tamar Serapian and Anuradha Prakash (July 27, 2015):
Abstract Body:
Strawberries are a highly perishable fruit with a short shelf-life especially at ambient temperatures. The study simulated commercial airfreight shipment of strawberries to Asian markets following phytosanitary treatments and evaluated the marketability of strawberries kept under ambient temperature retail conditions. Amado and Marquee strawberries were treated with methyl bromide fumigation (2 h at a concentration of 32 g/m3 at 21°C followed by degassing for 4-5 h) or gamma irradiation (400Gy). The strawberries were wrapped with insulated foil and ice packs for 24 h to mimic air shipment then maintained at ambient temperature until the end of shelf-life. Maximum ambient storage for all treatments was 3 days following treatment, however berries treated with methyl bromide exhibited the highest occurrence of mold/decay by end of shelf life. Irradiated berries were an average of 20% softer than fumigated strawberries and 23% softer than control fruit, however, consumer sensory panels showed no difference in liking for irradiated, fumigated, or control strawberries. Titratable acidity, soluble solids content, color values, and ascorbic acid content were unchanged due to treatments or storage time. As use of methyl bromide is phased out, low dose irradiation offers a good alternative for phytosanitary treatment of exported strawberries. 
Also in the News: Oyster scare hurting Eustis restaurant
.  (August 8, 2015):
EUSTIS, FLORIDA: Chet Pando knows oysters, he lives oysters and has been selling them profitably for 18 years.


So it wasn't easy for the owner of the Oyster Troff to toss 500 pounds of them into a dumpster Thursday. The Bay Street restaurant, which Pando said has shucked about 10 million oysters since it opened in 1998, has been hit hard by a recent newspaper article saying a Lake County resident contracted vibrio vulnificus after eating a contaminated oyster - six weeks after a 26-year-old Fruitland Park man died from the same bacterium.


The Florida Department of Health, which tracks these cases by county of residence, will only say someone got sick but fully recovered after eating a bad oyster. No other information - including the person's name, age, sex or where the illness was contracted - is released due to privacy issues.

The man who died, Cason Yeager, was diagnosed with an autoimmune disorder 10 years ago and contracted the bacterium after stepping on oyster shells while swimming in the Gulf of Mexico, his family said. Vibrio vulnificus is a rare bacterium, health officials said, putting people with autoimmune issues at risk if they eat raw oysters or cut themselves on their shells.


According to the Centers for Disease Control and Prevention, vibrio vulnificus lives in warm seawater and is in the same family as cholera. The bacterium is part of a group of vibrios that are called "halophilic" because they require salt.


Not publicizing where the Lake County resident got his bad oyster bothers Pando, who has seen sales drop because people are scared of eating raw oysters now.


"It's a serious slowdown," he said. "Oysters represent 50 percent of my business."

The person who got sick could have found a bad oyster in brackish water in the Gulf of Mexico because Pando doesn't believe a restaurant was involved. "I don't know where he got it - I have no idea," Pando said. "All of the major players in the industry don't have a clue about it. So that means there was no oyster recall and that speaks volumes. "See, the oyster processors would know because they're the ones that ship the stuff. They bag it, tag it, box it, ship it. They would have to know because they would be contacted. So, I don't know where this guy got his oyster."

Oyster bars like the Oyster Troff have to get their oysters from processors.

 

"They must go to an oyster processor in the state of Florida," Pando said. "They have to do things under the laws, and Florida has some pretty tight laws on oysters." For example, harvested oysters have to be brought down to 55 degrees within one hour of entering the processing plant, Pando said. The temperature is reduced further to between 35 and 41 degrees and if a shipped oyster arrives as a restaurant over 46 degrees, it has to be rejected.


The oysters are bagged and tagged so officials know exactly when and where the oysters were harvested. "The Department of Agriculture is right there when they come in," Pando said of the verification process. All of this is necessary in case a bad oyster hits the marketplace and a recall is necessary, Pando said.


"Biologists are in the water the next day," he said. "They're pulling out samples of the oysters, they're pulling out samples of the fish, mussels, the water ... Their biggest fear is having a massive outbreak." Besides having to deal with the Florida Department of Health over issues about storage, temperature and preparation of food products, restaurants like the Oyster Troff have oyster rules, too.


The state requires Pando to keep his oyster tags on hand for inspection for 90 days.

"I got over a year's worth," he said. State law also says no oyster can be sold after two weeks of harvesting. "I don't even like having them a week," Pando said. "I like to turn my stuff every two days."


The slowdown in sales has not only hurt the Oyster Troff's bottom line, but it has affected Pando's dozen or so employees - especially servers who rely on tip money. "I'm in the oyster business," he said. "It's not just one item on my menu."


Pando said the Oyster Troff is the biggest oyster bar in Florida in terms of seats. Since opening, he's gone from one to three oyster bars under one roof. Pando said some of his loyal customers are still eating raw oysters because they know he works closely with his processors and actually has visited their plants. He also knows his oysters and will gladly show someone the difference between the four varieties he sells.


"My customers know they're fresh," he said. Pando hopes that getting the message out about oyster safety guidelines will ease his customers' concerns and get them to belly up to the bar again. "This is my livelihood," he said. "It's my family's livelihood.

Link to article...

Radurafoodirradiation.org is an excellent source of information on food irradiation.

Food Irradiation Update is published by Ronald F. Eustice and sent to you through the sponsorship of GRAY*STAR, Inc., the manufacturer of the Genesis Irradiator. 
 
 
Food irradiation is a cold pasteurization process that will do for meats, produce, and other foods what thermal pasteurization did for milk decades ago.
Ronald F. Eustice, Consultant
Phone: 612.202.1016
reustice@gmail.com 
Ronald F. Eustice | 13768 Trost Trail | Savage, | MN | 55378

 



 
 

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